Absorption apparatus



Cd. 9, 1934. E. ALTENKIRCH I 1,976,593

ABSO RPTIGN APPARATUS Fil ed April 13 1926 s sheets-sheet 1 Oct. 9,1934.EmALTENKIRCH 1, 7

ABSORPTION APPARATUS Filed April 13 1926, 5 Sheets-Sheet 2 Oct. 9, 1934.E. ALTENKIRCH 1,976,593 ABSORPTION APPARATUS Filed April 13 1926 5Sheets-Sheet, 3

Oct 9, 1934. v E. ALTENKIRCH v 1,976,593

ABSORPTION APPARATUS Filed April 15/1926 5 Sheets-Sheet '4 Oct. 9, 1934."E. ALTENKIRCH ABSORPTION APPARATUS 5 Sheets-She et 5 Filed April 15,1926 Patented Oct. 9', 1934 1,976,593 Ansoarriom APPARATUS EdmundAltiznkirch, Alt-Landsberg-Sud, Germany, assignor, by mesne assignments,to The Hoover Company, North Canton, Ohio, a corporation of OhioApplication April 13, 1926, Serial No. 101,745

77 Claims.

In certain respects, the present application relates back to mycopending application Serial No. 99,890, filed April 5, 1926.

This invention relates to heat transfer means a and methods, in certainphases to refrigerating apparatus, and more particularly to an apparatusof the continuous absorption type in which an auxiliary agent (sometimescalled a neutral or inert gas) is employed as an aid to the-,main

heat transfer agent (sometimes called the cool- 2 ing agent orrefrigerant) in carrying out the heat transfer process.

It will be readily understood that, although the following descriptionthe invention is considered largely from the viewpoint of refrigeration,many features herein presented are not limited to this particular field.For simplicity in description, however, the terms commonly used in therefrigeration art, will be employed. It is an object of the invention todevise a new method and a new apparatus which have certain advantagesover known methods and apparatus particularly in the circulation anddisposi-.

tion of fluids. In one important phase of the invention, it relates tothe circulation of a solution of the refrigerant through the evaporationchamber or expeller of the apparatus.

Another object. of the invention is to provide apparatus for allocatingthe fluids to the proper 3o parts of thesystem.

It is a further object of the invention to provide a novel method and anovel apparatus of the type just mentioned and which uses an auxiliaryagent which is; inert with respect to the main refrigerant an theabsorbent. By circulating the auxilia gent through the evaporator andabsorber .--a certain way, various economies and advantages areobtained.

It is another object to devise means and meth- 0d for producingrefrigeration substantially at atmospheric pressure.

In accordance with a major phase of the invention, I make use of aneutral gas into which the absorbable niedium or refrigerant evaporatesout of the absorption liquid in the evaporator. The refrigerant isthereafter reabsorbed by the absorption liquid in another part of theapparatus. It iseven possibleto operate the apparatus substantially atatmospheric pressu'reand the vessels and pipes forming the various partsneed not be sealed from the atmosphere.

Further objects, advantages and applications -'-.pa"r ent as thedescription proceeds.

(mica-119.5

In the drawings afflxed to. this specification and forming part thereof;several forms of apparatus embodying my invention are illustrateddiagrammatically by way of example. In the drawings,

ing apparatus according to the invention;

. Fig. 1 is a diagram of an absorption refrigerat- Fig. 2 is a showingof an actual apparatus opcrating on the principles of the invention asdiagrammatically illustrated in 1;

Fig. 3 is a vertical section, and

Fig. 4 is a horizontal cross-sectional view of anabsorber adapted foruse in apparatus embodying the invention;

Figs. 5 and 6 are a plan view and cross-section, respectively, of thecooling pipe forming part of the absorber;

Fig. '7 is a vertical section of the evaporator, and

Figs. 8 and 9 are plan views of two of itsparts;

' Fig. 10 is a. vertical section of the gas rectifier;

Fig. 11 illustrates the shape of the disc partitions; I

Fig. 12 is a longitudinal section of the circulation nozzle;

Fig. 13 is a longitudinal vertical section reabsorptive device,

Fig. 14 being a cross-section thereof 'on the line A-B in Fig. 13; and

Fig. 15 is a diagram of an absorption apparatus adapted for raising thetemperature. v

Referring first to Fig. 1, a continuous absorption refrigerating systemis there shown as consisting of an evaporator or expeller 1-, anabsorber 11, a boiler or expeller (sometimes also called generator) 15and a second. absorberorresorber 8, as essential elements, these partsbeing connected by various conduits asshown. The total pressure issubstantially the sarne throughout the system,

will be assumed that these substances are used,

as they are preferred, but various other substances may be used .as isapparent to those skilled in the art.

The air is confined to the evaporator 1, ab-

sorber 11 and the conduits. 3 and 4 connecting these vessels forcirculating the air between them.

A solution of ammonia in water is supplied to the evaporator or expeller1 by the conduit 10 and refrigeration is produced in this chamber by theevaporationoj the ammonia out of the solutiontherein into mean. Thechamber 1 may contain a coil of pipe 2 or the like, for bringing aliquidto be cooled into proximity with the evaporating ammonia so that as the'evaporationta'kes place, heat may be transferred from the liquid in thepipe 2 to the fluids in the evaporation 4. fll'he weak ammonia solution,being now heavier, descends through the pipe 5 and, at the base of coil7, comes in contact with the ammonia gas which is admitted throughthepipe 6. The ab-.

sorption liquid, carried along by gas bubbles, as cends through theinclined helical pipe '7 without substantial quantities of the ammoniagas being absorbed since the pipe 'l'is not cooled. In the resorber 8provided with the cooling'coil 9, the ammonia gas is absorbed by thesolution and the strong solution, now being lighter ascends again intothe evaporator 1 through the pipe 10. .The resorber 8 is merely-a devicefor bringingthe ammonia gas and the water solution leaving theevaporator into intimate contact, while cooling the same so as to cause.the ammonia to be absorbedr Insofar as thisvessel itself is concerned itmay be iikeany known absorber.

The air with a large content of ammonia gas flows from the evaporator 1through the pipe 4 to the absorber 11. Weak absorption solution issupplied to the absorber 11 through the pipe 12. ,7

This weak solution absorbs ammonia from the gas 1 mixture. Theabsorptionheat developed as a result of this absorption is removed by the coolingcoil 13. The air, to great extent deprived of the ammonia gas, returnsinto' the -'evaporator 1 through the pipe 3. The absorption solution,

. which has been enriched with gas fin the absorber "of a helicallywound inclined tu the lower end which is heated by an electric heatingrod 16., Owing tov the increase in the temperature-the ammonia gas isexpelled from the solution. Hence the tube is called a boiler orexpeller. The ascending gas bubbles carry the liquid upwards into a gasseparator 17 in which--gas and liquid separate. The gas is conducte"into the helical tube 7 through the pipe 6 to e absorbed by theresorber solutionas explained above while the absorption solution fromwhich the gas has been expelled ascends into the absorber 11 through thepipe 12. Thus evaporation occurs in the vessels 1 and 15 and absorptionoccur'sin the vessels 8 and 11.

11, is conducted through pipe 14 Due to the presence of the air in theevaporator 1, the evaporation in this vessel takes place at a much lowertemperature than the evaporation in the boiler 15. In accordance withwell known laws of partial'pressure, the total pressure in theevaporator 1 is the sum of thepressure due to the air and that due tothe ammonia; therein. Hence it may be said that the pressure of therefrigerant in the expeller 15 is considerably higher than that in theexpeller 1. Likewise,- in the absorbers 8 and 11, the refrigerantpressures are quite different due to the air in the absorber 11, theabsorber 8 having -the higher refrigerant pressure in this It shouldalso be noted that although the temperature diflerence between the two'expellers may be great, the expeller 1 being the point of lowesttemperature in the system and the exing water.

peller 15 the point of highest temperature, the two absorbers operate atabout the same temperature somewhere near the temperature of the cool-The level of the liquid in the absorber 11 is above the level of theliquid in the gas separating chamber 17 by the distance H. A higherpressure consequently prevails in chamber 1'7. This pressure differenceis utilized to supply refrigerant gas to nozzle 18, the supply pipe 19being branched ofi from the pipe 6 conducting the gas. The nozzle 18 islocated near one end of a venturi 20 in the gas pipe 4 and keeps the gasmixture flowing. therein. Thus the flow of gas is produced 'due to forcewithin the system. For actuating this nozzle a pressure difference ofless than 0,1 atmosphere is suflicient. The height- H need therefore notexceed 1 meter.

An important advantage of my invention resides in the fact that theconcentrations are so chosen that the absorption in the re-absorber' 8and the expulsion in the boiler 15 take place approximately atatmospheric pressure. The quantity of neutral gas admixed in theevaporator 1 and the absorber 11 is so proportioned that approximatelythe same pressure prevails in these vessels also, except for the smalldifference in pressure which is necessary for operating the n'ozzle 18in the gas circulation system, as explained above.

A U-tube 21 may be connected to the pipe .3 and filled with a'suitableliquid in its lower portion ,,ume, in the unit.

,The entire apparatus consistsv preferably of 1' vessels or containersand pipes, all welded ether. The U-tube may be made of glass or be atleast equipped with transparent portions to permit inspection of thelevels of the liquid therein which would indicate the pressure withinthe unit.

The actual construction of an apparatus according to the diagrammaticrepresentation in Fig. 1 is'shown by way of example in Figs. 2 to 14.

Referring to these figures, the boiler or expeller or generator consistsof. two helically wound pipes 60 and 61,-the axes of. which are disposedobliquely and which are heated by electric heating rods 62 and 63. Thehelical pipes open into'a gas separator 64 upon which is mounted'avertical pipe 65 which forms part of a rectifier, which is separatelyillustrated in its details and on an enlarged scale in Figs. 10 and 11.flows-through the pipe 66 into a heat exchanger formed by the inner tube67 and the outer tube 68. From the heat exchangerthe solution isconducted into the upper part of the absorber '70 through the pipe 69.\This absorber is illustrated in its details in Figs. 3 to 6 on anenlarged The gas empoverished absorption solution 1 scale. From thelower part of absorber 70, the

'the pipe'l2 and passes into the lower end of the wound and locatedobliquely. Simultaneously,

weak absorption solution flowsinto this pipe from the pipe '74. The gascarries the liquid through; the elevating pipe and the adjoiningstraight pipe '75 into the resorber 76 which is specifically illustratedin the Figs. 13 and 14. In the re- I sorber,'the ammonia supplied by theconduit '72 is largely absorbed in the absorption liquid. In otherwords, the ammonia gas is changed to a more dense fluid phase therein.After the solution has absorbed the gas here, it passes through the pipe77 into a heat exchanger which is formed by the outer pipe '78 and theinner pipe '79. It flows through the outer pipe '78 and the pipe 80 intothe evaporator 81. This evaporator is illustrated in its details inFigs. '7, 8 and 9. After the gashas been expelled from the liquid here(by the ,heat furnished by the evaporator surroundings), theempoverished liquid returns through the pipe 82, the inner pipe '79 ofthe heat exchanger and the tube '74 into the elevating'pipe '73. Ther-csorber '76 together with a vertical tube 83 also acts as a receiverfor any refrigerant gas not absorbed or for any; inert gas which mayhave found its way into the vessel '76. The conduit 84 provides a ventfor this gas back to the inert gas circuit, the vent 84 being connectedto the gas conduit 85. In the conduit 85 the ammonia gas-air mixtureflows from the evaporator 81 into the absorber '70. In the vertical pipe83. the liquid stands at about the level of t e top of i the pipe 80within the evaporator 81, (see Fig. -'7) Gas bubbles which have not beenabsorbed by the liquid, ascend in the vertical pipe 83 and are able toescape through the ventpipe 84. The current of air enriched by ammoniavapor passes from the evaporator 81 through the pipe 85 and the pipe 86into the absorber '70 and returns through the pipe 87 into theevaporator 81. In the pipe 86, the nozzle is arranged as shown in Fig.12. It is fed from the rectifier through the pipes 88 and 11-1. Joinedto the upper end of the evaporator 81 is the u -tube 89 similar to theLiv-tube 21 of Fig. 1. If the rectifier 65 does not separate and detainthe water vapor compl-etely, a portion of the water is thus boiled outof and travels gradually from the expeller pipes 60 and 61 by way ofpipe '72 and elevator '73 into the re-absorber '76 and hence by way ofpipes '77. '78 intc the evaporator 81. 'As soon as the level ofthe'liquid rises in the evaporator to such a height that it flows intothe gas circulation pipe 87, it is able to return into theexpellersystem through the drain pipe 90 terminating in pipe '71. Prcrto its entry into the pipe 90, the liquid is in contact with air of lowammonia content along. a comparatively long path in the pipe 87, andtherefore the ammonia which may still be contained in this overflowliquid has ample oppor tunity to separate, so that almost water onlyreturns intothe other system,

The absorber '70 is shown in vertical crosssection in Fig. 3 and inhorizontal cross-section in Fig. 4. It consists essentially of thecasing- 91 having abottom 92 and a cover 93. A pipe 96 traversed bycooling water is sinuously wound in numerous planes within the absorber.The cooling water enters at the top and escapes at the bottom. The gasempoverished absorption solution enters through the pipe 69 which isbent I in a circle within the absorber and is provided with a pluralityof perforations .at the underside, which are indicated in dotted linesin Fig. 4. The solution drips onto the cooling pipe 96. In

order tospread the solution over as large a surface as possible a broadwick 9'7 is braided over the windings of the pipe 96, which is notillus-' tratedin the Figs. 3 and 4.1 Fig. 5 shows the sinuous windingsof the pipe 96 in one plane in plan. The wick 9'7 braided around thewind ings is shown in Figs. B and 6. The strong ammonia gas mixture'enters through the pipe 86 and flows upwardly through the absorber,coming in intimate contact with the wick 9'7 saturated with liquid whichlatter-absorbs the ammonia. The empoverished ammonia gas mixture leavesthe absorber through the pipe 8'7 and flows to the evaporator (Fig. 2).

The evaporator is shown in cross-section and on an enlarged scale in '7.Figs. 8 and 9 show constituent parts in p an. The evaporator includes acylindrical shell 98 with end' walls 99 and 100. 'The shell is equippedwith insertions 101 and 102 in its interior which are shown.

103 spaced equidistant from the disc' center.

Each insertion 101 is displaced with respect to the adjacent insertion102 so that the openings 1 103 in adjacent discs are displaced by 90 derees,

as indicated in Fig. 9. Above the insertions is located a sheet-irondish 105, which is shown in plan view in Fig. 8. It is provided withnumerous perforations 106 which are just sufficiently large to allow theliquid contained in the dish 105 to issue in,drops. Theliquid issupplied to the dish by a central pipe 80. It drips from insertion toinsertion through the evaporator and escapesthrough the pipe 82. Thecurrent of gas weak in ammonia enters through the pipe 8'7 and escapesthrough the pipe" 85. As it is obliged to take its way through theopenings 103 in staggered arrangement, it sweeps along the insertionssaturated with liquid and thus absorbs ammonia from the liquid. The heatof evaporation necessary for this is withdrawnthrough the evaporatorwall 98' from the surroundings of the evaporator 81 to be cooled.

The interior of. the evaporator communicates with the atmosphere throughthe pipe 89, separated from it through a liquid seal only as shown 'in'Fig. 2. It is important that the stream of ammonia enriched neutral gasentering at the bottom flows through the evaporator in oppositedirection to the direction of flow of the absorption solution drippingdown from above, because the solution which has reached the bottom iscomparatively poor in ammonia and can therefore only give off ammoniagas. at a lower ammonia pressure. This lower partial pressure isobtained as the result of the entrance of the practically pure air atthe bottom.

The rectifier 65 is shown in cross-section in i Fig. 1 0. It includes avertical pipe in which are located sheet iron discslo'l. In Fig. 11 sucha disc is shown in plan. As clearly shown in the drawings, a section isout ofi from the discs so that suflicient space is left for the gasflowing past; Any two adjacent discs 10'? are displaced in relation totheir cut away portions by an angle-of 65 a cooling coil 108 isarranged.

Fig. 12 shows the pipe 86 and a portion of the tube 85 in cross-section.Into the pipe 86 is in- In the upper portion of the rectifier Y serted aventuri 109 intowhich vaporous refrigerant is blown through the nozzle110. The

nozzle is fed with a pipe 111, which, comi from the rectifier 65, firstpasses from the pipe 88 into a jacket112 which surrounds the pipe 85.This pipe is traversed by the cold ammonia-neutral gas mixture comingfrom the evaporator 81 and thus cools the ammonia vapor passing throughthe pipe 88 still further than itis cooled in the rectifier 65 and socondenses stillfurther quantities of admixed water vapor. The condensedWater flows back through the pipe 88 into rectifier 65.

The resorber is illustrated in Fig. 13 in longitudinal section and inFig. 14 in cross-section along the line A-B in Fig. 13. It consistsessentially of a cylindrical shell or housing into which is inserted acooling coil 113, and of the vertical pipe extension 83surrounding thestraight portion of pipe 113. The cooling water enters at 114, flowsfirst through the straight part 95 of the cooling pipe which is locatedwithin the vertical pipe 83, and then flows through the cooling coil 113and escapes at 115. The cooling of the vertical pipe 83 serves thepurpose of avoiding an evaporation in the column of liquid standinghere. Vaporous ammonia and absorption liquid, supplied jointly throughcoil '73 (Fig. 2), fiows through pipe '75 into the resorber '76 whereboth issue through bores 116. The ammonia enriched solution leaves there-absorber through the pipe '77. Quantities f of ammonia which may'nothave absorbed can escape through the pipe 84 which, as Fig. 2 shows,leads into pipe 85 in which it is admixed to and.

further enriches the ammonia-gas mixture coming from the evaporator.

Another embodiment of my invention is the absorption apparatusillustrated diagrammatically in Fig. 15. It 'serves the purpose to raiseexisting quantities of heat of medium temperature to a highertemperature at which they may vbe utilized. These quantities of heatmay, for

instance, be contained in waste waters of medium temperature. The wastewaters are conducted through the coil 31 located in the evaporator 3'1and the heating vessel 32 which surrounds the expeller or boiler 45 ofthe system. A part of the heat is thus given up by the water andtherefore its-temperature is lowered. This raises the temperature of theevaporator and. expeller and causes it to function. The heat of lowertemperature is absorbed by the cooling water in the coil 33. The usefulheat of the desired higher temperature is transmitted to a liquid whichis passed through the coil 34 for the purpose oi heating it. This coilis located in the interior of a resorber 35 into which is conducteda'mixture of ammonia gas and water. By the absorption of the ammoniagas, the heat of higher tem-' perature to be transmitted 'tothe coil 34is generated. The absorption solution thus enriched by gas ascendsthrough the pipe 36 into the evaporator 37. Here heat of mediumtemperature of thewaste. water is supplied to it by the heating coil 31.The solution comes, furthermore, in con tact with a stream of air poorin ammonia which enters the vessel 3'7 through the pipe 38. The

partial pressure of the ammonia in this gas mix-' ture is so low thatthe ammonia is evaporated.

The air now enriched with ammonia escapesirom the vessel 37 through thepipe 39. The weaker I solution escapes through-the pipe 40 and againcomes in contact with gaseous ammonia which streams in through the pipe41. Gas and liquid .asce'nd into the resorber 35 through ahelically 7jwound pipe 42 1,976,593 onia vapor through the 1,

' ture weak, in

The air enriched with ammonia in the evaporator 37 passes into anabsorber 43 through the pipe 39. The absorption solution cooled by thecoil 33 again withdraws a portion of the ammonia from the gas mixtureand the gas mixmonia escapes again through the pipe 38. The strongsolution leaves the absorber 43 through a pipe 44 and enters a helicallywound boiler or expeller pipe 45. This pipe is located in the heatingjacket 32 and the gas is expelled by the supplied heat of mediumtemperature derived from the waste water. Gas and liquid ascendtogetherinto the. gas separating chamber 46 whence the weak solutionreturns into the absorber 43. through the pipe 47 while the expelled gasis supplied to the absorption solution flowing in the pipe 40 throughthe pipe 41. The gas pipe 48 which leads to the nozzle 49 is branchedoif from the pipe 41. The gas escaping here maintains the circulation ofthe gas mixture in the pipes 38 and 39 the same as previously described.The apparatus is in communication with the atmosphere by a U-tube 50,similar to the apparatus shown in Fig. 1, and is only separated from itby a liquid seal.

It will be apparent that the apparatus herein described is of thecontinuous absorption type, that is, it is capable of producingrefrigeration continuously without the necessity of manipulation anddoes not pass through cycles in which the functions of certain vesselsare changed from time to time as is common in the so called inter-'mittently operating absorption systems. Howneutral gas and causing thereabsorption of said medium by said liquid.

2. The method of causing variations of temperature which includesexpelling an absorbable medium from an absorption liquid directly into aneutral gasand causing the reabsorptionof said medium by said liquid,the operation being carried through substantially at atmosphericpressure.

3. The method of causing variations of temperaturewhich includesexpelling an absorbable medium from an absorption liquid into a neutralgas, causing the reabsorption of said medium by said liquid, andcirculating said liquid and said gas in counter currents.

4. The method of causing variations of temperature which includestransferring an absorb- .able medium from a body of absorption liquidinto a neutral gas, absorbing the transferred medium out of said gas byanother .body of absorption liquid, expelling the absorbed medium fromthe said other body of absorption liquid and reabsorbing the medium thusexpelled by said first .body of absorption liquid.

5. The method of causing variations of temperature which includestransferring an absorbable medium from a body of absorption liquid intoa neutral gas, absorbing the transferred medium from said gas by anotherbody of absorption liquid, expelling the absorbed medium from the saidother body of absorption liquid, reabrating the absorbed medium from theliquidconr said absorber and for returning ,such liquid into forcirculating liquid through said transferring i ature containing an ablemedium, a neutral gas and which includes culating means for separatingliquid and absorbsorber; 'said'vessel and said absorber each con-.

liquid into said absorber.

able by saidliquid, said vessel, absorber and duct,

- tion liquid directly into said neutralgas and means for causingmovement of the inert gas.

sorbing the; medium thus expelled by said [first means for body ofabsorption liquid and causing movement transferring means and saidabsorber, means for of the neutral gas. I circulating liquid throughsaid transferring 6. Apparatus for causing variations of tempermeans,means for circulating liquid through said absorption liquid, anabsorbabsorber,'means cooperating with said latter cirmeans fortransferring said absorbable medium able gas, and means for conductingabsorbable from said absorption liquid into said neutral gas gas thusseparated into contact with liquid cir-- substantially at atmosphericpressure and a liqculating through said transferring means. uid sealforming the only means for separating 13. Apparatus for causingvariations of temperthe interior of said apparatus from the outer air.ature containing an absorbable gas and neutral '7. Apparatus for causingvariations of temperg%, and including a gas transfer vessel containingature comprising a vessel acting as evaporator absorption liquid andhaving means for transferand gas transfermeans, an absorber, acommunication duct between said vessel and said abring absorbable gasinto said neutral gas, an absorber containing absorption liquid, meansfor taining absorption liquid and a medium'absorbable by said liquid,said duct containing a'neutral gas and means outside of said absorberfor sepasaid absorber, means for circulating absorption liquid throughsaid transfer vessel, means for cir-, culating absorption liquid throughsaid absorber,

I ,means cooperating with said latter circulating tained in saidabsorber and for returning such means for separating liquid andabsorbable gas,

i means for conducting absorbable gas thus sepa- 8. Apparatus forcausing variations of temperrated into contact with liquid circulatingthrough ature .comprising avessel acting as an evaporator said transfervessel and means in the latter cirand as a gas transferring means, anabsorber, a cuit for causing the reabsorption of saidabsorbcommunication duct between said vessel and said able gas broughtinto contact with the absorption absorber, said vessel and said absorbereach conliquid. taining absorption liquid and a medium absorb- 14.Apparatus for causing variations of temperature containing two bodies ofabsorption containing a neutral gas, means for causing the liquid, andabsorbable medium and a neutral gas expulsion of the medium from theabsorption liqin contactwith said two bodies, and including uid in saidvessel, means for causing the absorbmeans for transferring absorbablemedium from tionof the medium by the absorption liquid insaid one ofsaid bodies into said neutral gas,.an abarating the absorbed medium fromthe liquid in said transferring means and said absorber, means saidabsorber, and means fo r'returning said mefimeans, means for circulatingliquid through said dium into contact, outside of said transfer vessel,absorber, means cooperating with said latter sir-.-

with the liquid, from which it is-e ipelled in said culating means forseparating liquid and absorbvessel. I able gas, means "for; conductingabsorbable gas 9. Apparatus for causing variations of 'te mperthusseparated into contact with liquid circulatature containing anabsorption liquid, an absorbing through said transferring means andmeans circulating neutral gas between said vessel and absorber, meansoutside of. said absorber for se'psorber, means for circulating neutralgas between able medium, a neutral gas, and including means in thelatter circuit for causing reabsorption of for transferring said mediumfrom said absorpsaid absorbable gas in said latter liquid.

15. Apparatus for causing variations of tem- 10. Apparatus for causingvariations of temsorbable medium, a neutral gas and having meansperature containingtwo bodies of absorption liqfor transferring saidabsorbable medium from uid, an absorbable medium and a neutral gas insaid absorption liquid into said neutral gas, said contact with saidtwobodies, and including means transfer means including means for finelydividfor transferring absorbable medium from one of ing said liquid andmeans for conducting the said bodies into said neutral, gas and meansfor liquid so divided into intimate contact with said projectingabsorbable medium derived from the neutral gas;

. f, r I i j 16. Apparatus for causing variations of tem- 1l Apparatusfor causing variations of temperature containing an absorption liquid,an abperatur'e containing an absorbable gas and a neu' sorbable medium,a neutral gas and having means other. of said bodies into said gas,

I t a a a including ea t1f1m$ferringfor transferring said absorbablemedium from contact with said two bodies, and including means absorbablegas into said neutral gas, an absorber said(aR5orption-1iquid into Saidneutral gas, Said containing an absorption liquid, meansfor circulatingneutral gas between said transferring means a seldflbsirberi means,mmula? liquid so divided into intimate contact with said absorptlon hqmdthrough sald transien'n! utral gas and means for conveying heat frommeans, means for circulating absorption liquid without to Sam 1i qui dwhile in a finely divided throug ing sad liquid and means for conductingthe uid and absorbable gas, and means for conduct-" hqmd' j ingabsorbable gas .thusseparated into contact Apparatus for causmgvanatlons of with liquid circulating through said transferring me'ans.-i

12. Apparatus for causing variations of tem- I said absorption liquidinto saidneutralgas, said transferring means including perforate heatcoriductive metallic bodies and porous material asfor transferringabsorbable medium from one of sociated with the said bodies forfinelydividing said bodies into said .neutral gas, an absorber, said liquid,and means for conducting said,gas

uid, an absorbablemedium and a neutral gas in perature containing anabsorption liquid, an ab-.-

transgzfr means including means for finely divid- Said i g ggiz gg agsggi gzgg ggfi figf stateto remove the'absorbable medium from theperature containing'anabsorption liquid, an absorbable. medium, aneutralgasand having means for transferring said absorbablemedium fromthroughsaid bodies and material, to mix'with said medium freed from the liquid.

18. Apparatus for causing variations of temperature includi atransfervessel, an absorber,

a communication between said vesseland said absorber, said transfervessel and said absorber each containing a body of absorption liquid anda medium absorbable by said liquid, and a neutral gas in said vessel,absorber and communication, means for circulating each liquid bodythrough its respective container, means operating for separating theabsorbed medium from the absorption liquid and for returning theempoverished liquid into said absorber, the body of absorption liquid insaid transfer vessel having a higher concentration of absorbable mediumthan the body of absorption liquid in said absorber.

19. Apparatus for causing variations of temperature, containing anabsorption liquid, anabsorbable medium, a neutral gas, and including anevaporating vessel for transferring'said absorbable medium from saidabsorption liquid into said neutral gas, and means comprising anabsorption vessel for lowering the partial pressure of said medium inthe neutral gas-medium mixture to permit the evaporation of said mediumin said first-named vessel.

20. Apparatus for causing variations of temperature containing anabsorption liquid, an absorbable medium, a neutral gas, and including anevaporating vessel for transferring said absorbable medium from saidabsorption liquid into said neutral gas, means for withdrawing theabsorbable medium from said neutral gas, thus lowering the partialpressure of said medium in the neutral gas-medium mixture and permittingthe evaporation of said medium in said first-named vessel and means formaintaining a pressure in said evaporating vessel substantially equal tothat of the atmosphere.

21.- The method ,of producing refrigeration including the steps ofcirculating an absorptionsolution into and out of an evaporating vessel,charging the absorption solution with a. refrigerant ata point outsideof said-vessel and circulating a gas into and out of the evaporatingvessel to maintain the refrigerant at a low partial pressure in thevessel and thus cause the same to be expelled from the absorption liquidin said vessel.

22. The method of producing refrigeration includingthe steps ofconveying an absorption liquid charged with a refrigerant into anevaporator and causing the refrigerant to be expelled from'theabsorption liquid by maintaining a partial pressure of'refrigerant and apartial pressure of an auxiliary gas in the evaporato r'.

23. Refrigerating apparatus including means for. conveying an absorptionliquid intoan evaporator, means remote from said I evaporator forcharging said liquid with refrigerantand means for circulating an auxiliry gas into and out of the evaporator thereby maintaining a low partialpressure of refrigerant therein.

24. In a refrigerating apparatus of the 'continuous absorption type, thecombination of a generator, an absorber, an evaporator, a secondabsorber connected to said evaporator and containing an absorptionliquid and means operable by gas pressure for causing said absorptionliquid to circulate between said second absorber and said evaporator.

25. In a refrigerating apparatus of the continuous absorption type, thecombination of a generator, an absorber, an evaporator, a secondculating system. a

absorber connected to said evaporator and con-- taining an absorptionliquid and means operable incident to the lifting action of a gas forcirculating said absorption liquid between said second absorber and saidevaporator.

'26. In absorption refrigeration apparatus, the combination with aboiler system including a gas separating chamber and an absorber of arectifier,

ing a generator, an evaporator, an absorber, a

system for circulating an absorption liquid between said generator andabsorber, a conduit for conveying gas'from the evaporator to theabsorber, a' conduit for conveying gas from the absorber to.theevaporator and means independent of said last mentioned conduit fordraining absorption liquid which collects therein back into saidabsorption liquid circulating system.

28. Refrigerating apparatus including. a generator, an evaporator, anabsorber, a system for circulating an absorption liquid between saidgenerator and said absorber, a system for circulating an inert gasbetween the evaporator and absorber and including a gas conduitconnected to the top.

part of the absorber and having a portion located near the lower part ofthe evaporator and means for draining absorption liquidvwhich collectsin said conduit back into said absorption liquid cir- 29. Absorptionrefrigerating apparatus including an absorber,an evaporator, and asystem for circulating an inert gas between said evaporator andabsorber, said system including a jet, means for supplying a gas to saidjet for driving .the inert gas and means for causing an exchange of heatbetween the gas supplied to the jet and the'inert gas passing from theevaporator to the absorber. 30. In a continuous absorption refrigeratingsystem, the combination with vessels constituting an evaporator and anabsorber, of means for causing liquids to flow downwardly in saidvessels and stationary means constituting a'flxed integral part of saidsystem for causing an inert gas to circulate between said vessels andpass upwardly in each so as to have a flow in the opposite direction tothe flow of liquids therein.

31. In a continuous absorption refrigerating apparatus, the combinationwith vessels constituting an absorber and an evaporator, of means forcausing liquids to flow therein and stationary means constituting afixed integral part'of said apparatus for causing an inert gas tocirculate between said vessels and pass through each of said vessels ina direction opposite to the direction of flow of said liquids.

32. A continuous refrigeratingsystem'having an absorption liquid circuitincluding a first vertically extending branch containing liquid, and asecond vertically extending branch containing. liquid, connections forflow of fluid between said branches, a vessel wherein application ofheat changes a fluid from a dense phase to gaseous form, and means toconduct gaseous fluid from .said vessel and introduce the same into saidfirst branch to lighten the fluid therein and cause circulation upwardlyin said first branch and downwardly in said second branch.

' tion system whi 33. That improvement in the art of continuousrefrigerating through the agency of an absorpconsists in evaporating acooling agent to for a gas, and mixing the gas with absorption liquidand circulating abfsorption liquid due to the introduction of vaporizedgas thereinto.

34. That improvement in the art-of refrigeration through the agency ofan absorption system including a plurality of circuits-of liquidcirculation which consists in developing gaseous fluid in one circuit,conveying the developed gaseous fluid to another circuit and introducingthe same 1 into the liquid therein to promote the flow of said liquidover its circuit.

35. Refrigerating apparatus comprising a generator, an evaporator, aconnection for flow of fluid from said generator to said evaporator, anabsorber interposed in said connection, means to force gaseous fluidfrom said generator into said connection, members for carrying fluidforming an absorption fluid circulation system between the generator andevaporator in parallel to said connection and a connection between theevaporator andabsorber.

'36. That improvement in the art of refrigeration through the agency ofan absorption system including an evaporator and an absorber whichconsists in generating force within the system, 30

forming a'solution in the absorber, conducting said solution from theabsorber into the evaporator due to said force, circulating asolvent'for one of the solution substances into and out of theevaporator and returning the other to the absorber due to said forcewhile maintaining said system under substantiallyuniform pressurethroughout. 1

37. That improvement in the art of refrigeration through the agency ofan absorption system including a generator, an absorber and anevaporator which consists in conducting fluid fromboth the generatorandthe evaporator -to the absorber, forming a solution in the absorber,-

conducting the solution to the evaporator and transporting one of thesolution substances from the evaporatorto the generator by absorptionfluid circulation.

"both the generator and the'evaporator to the 38. That improvement inthe art refrigeration through the agency of an absorption systemincluding a generator, an absorber and an evap-' orator which consistsin conducting fluid from absorber, forming a solution in the absorber,conducting the solution to the evaporatorand transwhich consists inintroducing a plurality of substances in solutionform into theevaporator, introducing an absorbent for one of said sub-' porting oneof the solution substances from the evaporator to the generator byabsorption fluid circulation while maintaining a. substantially constantpressure throughout the system.

39. That improvement in the art of refriger'ating through the agency ofan absorption system including interconnected evaporator and absorberstances intothe absorber, generating force within the system andcirculating fluid between the absorber and evaporator due to said force.

40. Refrigerating apparatus comprising a gen-' orator, an evaporator,two absorbers, conduits forming cycles of circulation between theevaporat'orand one absorber, betweenthe generator and said one absorberand between the evapo-' rator'and the other absorber, and a vaporconnection between said generator and said other absorber.

I 41; Refrigerating apparatus of the continuous operating absorptiontype,-characterized bythe fact that the'apparatus contains threesubstances all of which pass through the evaporator and all of whichpass through continuous cycles.

42. The process of refrigerating with an absorption system whichcomprises evaporating a liquid cooling agent in the presence of anauxiliary agent inert to the cooling agent and thereby producing agaseous mixture of the vapor of the cooling agent and the auxiliaryagent, creating a slight" pressure difference within the system,conducting said gaseous mixture under the influence of said pressuredifference into the presence of an absorption liquid, absorbing thecooling agent in the absorption liquid, withdrawing the absorptionliquid from the presence of the auxiliary agent, returning the auxiliaryagent into the presence of the cooling agent under the influence of saidpressure difference, heating. the.

absorption liquid and expelling the cooling agent from solution,returning the absorption liquid into the presence of the gaseousmixture, converting the cooling agent to more dense phase andreturning-the densified cooling agent into the presence of the auxiliaryagent, these several steps of the process taking place in an apparatusopen to the pressure of the atmosphere.

43. The improvement in the process of refrigerating by the aid of asystem including a cham--' ber wherein a-refrigerant may be evaporatedand a chamber wherein a refrigerantmay be absorbed which consists indiffusing a cooling agent in the presence of an auxiliary agent in theevaporation chamber, and circulating the auxiliary agent through theevaporation chamber and theabsorpagent in the evaporator, andcirculating the am;-

iliary agent through the evaporator and the absorber exclusively: byslight pressure differences created in the system, while maintaining theevaporator and the absorber open to the influence of atmosphericpressure.-

45. The process of refrigerating with an absorption system whichcomprises evaporating a liquid cooling agent in the presence of anauxiliary agent inert to the cooling agent at substantially atmosphericpressure and thereby forming a gaseous mixture of vapor of the coolingagent and the auxiliary agent, creating a slight pressure differencewithin the system, conducting said gaseous mixture' under the influenceof said pressure difference ing the absorption liquid from the presenceof the. auxiliary agent, returning the auxiliary agent into the presenceof the cooling agent under the influence of said pressure difference,heating the absorption liquid and expelling the cooling agent fromsolution, returning the absorption liquid into the presence of thegaseous mixture. converting the cooling agent to more dense phase atsubstantially atmospheric pressure, and returning the densified coolingagent into the presence of the auxiliary agent.

46-. The process of refrigerating with an absorption system whichcomprises evaporating a liquid cooling agent in the presence of anauxiliary agent to more dense phase and returning the densified coolinginto the presence-of the auxiliary agent, these several steps of theprocess taking place in an apparatus open'to the pressure of theatmosphere.

which consists in diffusing a cooling agent into air in the evaporationchamber, nd circulating the auxiliary agent through tge evaporationchamber and the absorption chamber, while maintaining the chambers opento the influence of atmospheric pressure. i

48. In an absorption refrigerating system having separate" vesselsconstituting an evaporator and an absorber, the improvement whichconsists in flowing a cooling agent downwardly through the evaporator bygravity, pressure difference within the system due to heat, circulatingan auxiliary agent through the evap0- rator and the absorber due to saidpressure difference, the auxiliary agent flowing upwardly in theevaporator, and retaining said cooling agent in the evaporator in aplurality of bodies of extended surface.

49. In an absorption refrigerating system having separate vesselsconstituting an evaporator and an absorber, the improvement whichconsists in flowing a cooling agent downwardly through the evaporator bygravity, generating force within the i system and circulating anauxiliary agent upwardly through the evaporator and upwardly through theabsorber due to said force.-

50. man absorption refrigerating system having separate vesselsconsituting an evaporator and an absorber,the improvement which consistsin applying heat to the system, flowing a cooling agent downwardlythrough the evaporator by .gravity, and circulating an auxiliary agentthrough the evaporator and the absorber" due to the heat applied to thesystem, the flow of the auxiliary agent being upwardly through theevaporator. i

51. Absorption refrigerating apparatus including an evaporator, anabsorber a plurality of con duits connecting said evaporator and saidabsorber to form a circuit for the circulation of an inert gas throughthe evaporator and absorber,- means for supplying absorption liquid tocircuit, means for withdrawing absorption liqui from said circuit,whereby some inert gas may be carried away from said circuit by theliquid leaving said circuit, means for expelling inert gas so carriedfrom the absorption liquid, means for receiving the gas expelled fromthe liquid, a connection for the flow of liquid from the receivingmeansto the evaporator extending downwardly and upwardly to form a liquidseal, and means to: vent the inert gas from said receiving means backinto said inert gas circuit. I

52. Absorption refrigerating apparatus including a resorber, anevaporator, an absorber. and

a boiler, means for conveying refrigerant vapor to said resorber, meansfor circulating an absorption'liquid through and between the resorberand the evaporator and for causing the refrigerant supplied to theresorber to be absorbed by the ab sorption liquid and be conveyed by theabsorption -liquid to.the evaporator, means using an inert erant to beabsorbed thereby and conveyed to the boiler and means for causingtherefrigerant to evaporate out of the absorption liquid in the boiler.

53. In an absorption apparatus, an expeller expeller is adapted toconvey the weak solution coming from the second expeller through saidascending pipe and a cooled chamber at the upper end of said ascendingpipe in which the absorption solution again absorbs the working agent.

54. A heat transfer system including two expellers, an absorber and adevice for changing a .gas, as a refrigerant'gas to a more dense fluidphase, means for conducting a gas from one expeller to said device,means for conducting a liq-' uid from said device to the other of saidexpellers, .means forconducting the gas from the last named expellerto-the absorber and means for circulating a liquid between the absorberand thefirst named expeller, the entire system being so arranged thatthe various parts operate at sub"- stantially the same total pressureexcept for dif-.

ferences due to liquid columns.

55. A device as'described in claim 54 in which the second named expellerand the absorber contain an inert auxiliary pressure equalizing agentsuch as air. r I 56. An absorption refrigerating system including aboiler, a resorber,.an evaporator and an absorber, means for conductingrefrigerant gas from said boiler to said resorber, means for circulatingan absorption liquid between said re- I sorbe and said evaporator toconvey refrigerant from the resorber to the evaporator, means using aninert gas for conducting refrigerant gas from the evaporator to theabsorber and means for circulat and the boiler to convey the refrigerantfrom the absorber to the boiler. v

57. An absorption refrigeratingsystem includabsorber, means forconducting refrigerant gas froms%ld boiler to said resorber, means forcirculating a absorption liquid between said resorber absorption liquidbetween the absorber ing a boiler, aresorber, an evaporator and anandsaid evaporator to convey refrigerant from e resorber to theevaporator, means for conducting refrigerant gas from the evaporator tothe absorber and means for .sorber, means for conducting refrigerantgas-fromsaid boiler tosaid, resorber, means for circulating anabsorption liquid between said resorber and said evaporator to I I I'resorber to the evaporator, means for conducting 'convey refrigerantfrom the and the auxiliary agent, generating force within the system,conducting said gaseous mixture unrefrigerant gas from the.evaporator-to the ab-" der the influence of said force into the presenceof an absorption liquid at substantially atmossorber and means forcirculating absorption liquid between the absorber and the boiler toconvey the refrigerant from the absorber to the boiler, the-variousparts of said system being arranged to operate at approximately the sametotal pressure except for differences due to liquid columns. 59.

An absorption refrigerating system including a boiler, a resorber, anevaporator and an absorber, means for conducting refrigerant gas fromthe boiler to the resorber, means utilizing the lifting action of therefrigerant passing from the v boiler to the resorberfor Circulating anabsorption liquid between the resorber and the evaporator to conveyrefrigerant from the resorber to the evaporator, means for conductingrefrigerant gas from the evaporator to the absorber and means forcirculating absorption liquid between the absorber and the boiler toconvey the refrigerant from the absorber to the boiler.

69. *An absorption refrigerating system including a boiler, a resorber,an evaporator and an ab- I sorber, means for conducting refrigerant gasfrom the boiler to theresorber, means for circulating an absorptionliquid between the resorber and the evaporator to convey refrigerantfromthe resorber to the evaporator, meansfor conducting refrigerant gasfrom the evaporator to the absorber and means for circulating absorptionliquid between the absorber andthe boiler to convey refrigerant from theabsorber to the boiler, said last mentioned means utilizing the liftingaction of the refrigerant passing from the absorber to the boiler.

61. In an absorption apparatus,. a system in which a gaseous workingagent is expelled from an absorption solution and again absorbed by thesolution, a second system in which the expelled gaseous working agent ischanged to a more dense vfluid phase and again converted into thegaseous form, and an ascending pipe through which liquid is conveyed bythegaseous working agent developed in one of said systems for thepurpose of maintaining the circulation of the liquid in the other ofsaidsystems.

62. In an absorptiorn apparatus, a systemin which a gaseous workingagent is expelled from an absorption 'solution and again absorbed by thesolution, a second system in which the expelled gaseous working agent ischanged to a more dense fluid phase and again converted into the gaseousform, and means adapted to enable the gaseous agent developed in one-ofsaid systems to effect the circulation of theliquid in this system aswell as in the other system.

-63. The improvement in the process of refrig-' erating by the aid of asystem including a part wherein a refrigerant may be evaporated and'apart wherein a refrigerant may be absorbed which consists in diffusing acooling agent in the presence of an auxiliary agent in the evaporationpart a a. gaseous mixture of vapor of the cooling agent 0 the coolingagent at substansure, and returning the densified tooling agent into thepresence of the auxiliary agent.

65. Refrigerating apparatus of the absorption type'including a gas andliquid separation memher, a plurality of vertically extending coilsarranged at about the same elevation, and means for circulating liquidbetween and through said gas'and liquid separation member and said coilsincluding means for causing lifting of,liquid by vaporous. fluid in saidcoils.

66. Refrigerating apparatus offthe absorption type including a gas andliquid separation member,,a plurality of thermosiphon lift members, andconnections forming a circulation circuit through said members in whichcirculation is produced by the lifting action of vaporous fluid in saidthermosiphon members.

67. Absorption refrigerating apparatusincluding a generator, anevaporator, an absorber, conduits forming a circulation circuit forabsorption liquid between said generator and said absorber,

conduits forming a circulation circuit for inert gas between saidevaporator and said absorber, and means for draining excess liquid fromthe evaporator including :a conduit separate from.

said gas circulation conduits.

. 68. Absorption refrigerating apparatus includinga generator, anevaporator, an absorber, conduits forming a circulation circuit forabsorption liquid between said generator and said absorber, conduitsforming a circulation circuit for inert gas between said evaporator andsaid absorber and extending above the bottom of the evap orator, andmeans for draining excess liquid from the evaporator to the. liquidcirculation circuit ineluding a conduit separate from said gascirculation conduits.

.69. Absorption refrigerating apparatus including a generator, anevaporator, an absorber, conduits formingv a circulation circuitforabsorption liquid between said generator and saidabsorber, conduitsforming a circulation circuit for inert gas between said evaporatorandsaid absorber and extending above the bottom of the evaporator,

evaporator through the gas circulation circuit into the liquidcirculation circuit including a conduit separate from said gascirculation conduits.

'70. In the art of refrigerating with a system employing a refrigerant,an absorption liquid and an inert gas and havingaliquid circulationcir-r cuitincluding a generator and an absorber, and

and means for draining excess liquid from the having a gas circulationcircuit including an evaporator and said absorber, the improvement whichconsists in draining excess liquid from the evaporator into the liquidcirculation circuit without passing through the absorber. v

71.'In the art of refrigerating with a system employing a refrigerant,an absorption liquid and an inert gas and having a liquid circulationcircult including a generator and an absorber, and

having a gas circulatioii circuit including an evaporator and saidabsorber, tthe improvement which consists in draining excess liquid fromthe evaporator into the gas circulation circuit to evaporate therein andthence to the generator without passing through the absorber.

'72. Refrigerating apparatus containing a refrigerant, absorption liquidand an inert gas and including an evaporator, an absorber, membersforming a liquid circulation circuit, conduits connecting the evaporatorand absorber to provide vertical flow of inert gas therethrough in thesame direction, and means actuated by 'force within the apparatus forcausing said fiow totake place in a predetermined direction.

73. Refrigerating apparatus containing a refrigerant, absorption liquidand an inert gas and including an evaporator, an absorber, membersforming a liquid circulation circuit, conduits connecting the evaporatorand absorber' to provide vertical fiow of inert gas therethrough in thesame direction, and means actuated by force within the apparatus torcausing said flow, to take place upwardly through the evaporator andupwardly through the absorber.

74. A refrigerating system including a vessel adapted to contain aliquid and wherein a gas may be formed from the liquid upontheapplication o-I heat thereto, a second vessel also adapted to contain aliquid and wherein a gas may be formed'from the liquid upon theapplication of heat thereto, an absorber, conduits connecting the firstmentioned vessel to said absorber to i'or'm a circuit for flow ofabsorption liquid be tween said first mentioned vessel and said absorber, and means to conduct gas out 0! one 01' said vessels and into aportion or said absorption liquid circuit outside of said firstmentioned vessel to promote the fiow of absorption liquid over saidcircuit.

'75. A refrigerating system having an absorption liquid circuitincluding a first vertically extending branch ciintaining liquid and asecond vertically extending branch containing liquid, connections forfiow of fluid between said branches, a generator, and means to conductgaseous fluid from said generator and introduce the same into said firstbranch to lighten the fluid therein and cause circulation upwardly insaid first branch and downwardly in said second branch. 7 a g 76. Thatimprovement in the art of refrigerating through the agency of anabsorption system including a generator, an evaporator and an absorber,said system containing a cooling agent and an auxiliary agent in thepresence of which the cooling agent evaporates, which consists inbuilding up a liquid column pressure gradient and circulating saidauxiliary agent between the absorber and evaporator due to said liquidcolumn pressure gradient. I

77. That improvement in the art of refrigerating through the agency ofan obsorption system including a generator, an evaporator and anabsorber, said system containing a cooling agent and an auxiliary agentin the presence of which the cooling agent evaporates, which consists inbuilding up a liquid column pressure gradient, circulating saidauxiliary agent between the absorber and evaporator due to said liquidcolumn pressure gradient and circulating dissolved cooling agent betweenthe generator and absorber. EDMUND ALTENKIRCH;

CERTIFICATE or Common,

Patent No. 1,976,593.

October 9. 1934.

EDMUND ALTENKIRCH.

It is hereby certified that error ification of the above numbered patentrequiring correction as follows: Line" 7,

date of filing, after "Serial No. 23, 1925; and that the said Letterstherein that the same may'conform to the Signed and scaled this 5th dayof February, A. D. 1935.

(Seal) Leslie Frazer Acting Conmioeioner oi Patcnt'l.

. cult including a generator and an absorber, and

having a gas circulatioii circuit including an evaporator and saidabsorber, tthe improvement which consists in draining excess liquid fromthe evaporator into the gas circulation circuit to evaporate therein andthence to the generator without passing through the absorber.

'72. Refrigerating apparatus containing a refrigerant, absorption liquidand an inert gas and including an evaporator, an absorber, membersforming a liquid circulation circuit, conduits connecting the evaporatorand absorber to provide vertical flow of inert gas therethrough in thesame direction, and means actuated by 'force within the apparatus forcausing said fiow totake place in a predetermined direction.

73. Refrigerating apparatus containing a refrigerant, absorption liquidand an inert gas and including an evaporator, an absorber, membersforming a liquid circulation circuit, conduits connecting the evaporatorand absorber' to provide vertical fiow of inert gas therethrough in thesame direction, and means actuated by force within the apparatus torcausing said flow, to take place upwardly through the evaporator andupwardly through the absorber.

74. A refrigerating system including a vessel adapted to contain aliquid and wherein a gas may be formed from the liquid upontheapplication o-I heat thereto, a second vessel also adapted to contain aliquid and wherein a gas may be formed'from the liquid upon theapplication of heat thereto, an absorber, conduits connecting the firstmentioned vessel to said absorber to i'or'm a circuit for flow ofabsorption liquid be tween said first mentioned vessel and said absorber, and means to conduct gas out 0! one 01' said vessels and into aportion or said absorption liquid circuit outside of said firstmentioned vessel to promote the fiow of absorption liquid over saidcircuit.

'75. A refrigerating system having an absorption liquid circuitincluding a first vertically extending branch ciintaining liquid and asecond vertically extending branch containing liquid, connections forfiow of fluid between said branches, a generator, and means to conductgaseous fluid from said generator and introduce the same into said firstbranch to lighten the fluid therein and cause circulation upwardly insaid first branch and downwardly in said second branch. 7 a g 76. Thatimprovement in the art of refrigerating through the agency of anabsorption system including a generator, an evaporator and an absorber,said system containing a cooling agent and an auxiliary agent in thepresence of which the cooling agent evaporates, which consists inbuilding up a liquid column pressure gradient and circulating saidauxiliary agent between the absorber and evaporator due to said liquidcolumn pressure gradient. I

77. That improvement in the art of refrigerating through the agency ofan obsorption system including a generator, an evaporator and anabsorber, said system containing a cooling agent and an auxiliary agentin the presence of which the cooling agent evaporates, which consists inbuilding up a liquid column pressure gradient, circulating saidauxiliary agent between the absorber and evaporator due to said liquidcolumn pressure gradient and circulating dissolved cooling agent betweenthe generator and absorber. EDMUND ALTENKIRCH;

CERTIFICATE or Common,

Patent No. 1,976,593.

October 9. 1934.

EDMUND ALTENKIRCH.

It is hereby certified that error ification of the above numbered patentrequiring correction as follows: Line" 7,

date of filing, after "Serial No. 23, 1925; and that the said Letterstherein that the same may'conform to the Signed and scaled this 5th dayof February, A. D. 1935.

(Seal) Leslie Frazer Acting Conmioeioner oi Patcnt'l.

